Chapter 7: Radio Frequency Distribution System; Rfds Theory Of Operation - Motorola DIMETRA MTS 2 Installation, Configuration And Basic Service Manual

Radio Frequency Distribution System
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This chapter contains the following topics:
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The Radio Frequency Distribution System (RFDS) distributes and manages the communications
network frequencies and mitigates interference between multiple radios, allowing them to
operate simultaneously. This results in improved radio reception performance across the
frequency ranges where multiple transmitters are broadcasting.

RFDS Theory of Operation

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The RFDS module is made up of the following subcomponents:
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The RFDS module supports the combining and filtering of multiple Base Radio transmitters to one or more
antenna outputs. The RFDS module supports up to triple receive diversity. Signals are filtered by either the
Duplexer or the Preselector, then amplified and distributed by the integrated Receiver Multicoupler (RMC). In
configurations with an Expansion Cabinet, the RX-splitter is used to distribute the received signal.
The RFDS also conditions the transmit and receive signal using filters. After combining the Base Radio
transmitters in the Hybrid Combiner (or in the Cavity Combiner in the case of the MTS 4), the transmit signals
are filtered in the transmit path of the Duplexer, which supplies the antenna connector on the cabinet.
6802800U74-N September 2009
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"RFDS Theory of Operation"
"MTS 2 RFDS"
"MTS 4 RFDS"
"Expansion Cabinet RFDS"
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Preselector (MTS 2 and MTS 4)
Duplexer (MTS 2 and MTS 4)
Cavity Combiners (MTS 4 and Expansion Cabinet)
Hybrid Combiner (MTS 2, MTS 4 uses either HC or CC)
Post Filter (MTS 4 only)
RX Splitter (Expansion Cabinet only)
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Chapter
7
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